This invention relates to a seeker head for target tracking missiles having an image resolving seeker being gimbal suspended in a seeker gimbal assembly and adapted to be aligned to a target by target deviation signals, and inertial sensors,
Target tracking missiles are known having an image resolving sensor, e.g. in the form of a detector matrix having a two-dimensional array of detector elements. This seeker is gimbal suspended in a seeker gimbal assembly. Inertial sensors respond to the angular movements of the missile in inertial space. Torquers act on the gimbals of the seeker gimbal assembly and decouple the seeker from the thus determined angular movements of the missile. An image of an object scene is generated on the detector matrix. Target deviation data of a target located in the object scene, e.g. an enemy aircraft to be attacked, are generated by image processing of this image. The target deviation data represent the deviation of the target from an optical axis of the seeker. By means of these target deviation data the seeker tracks the target. From the tracking the angular rate of the line of sight is determined. From the angular rate of the line of sight, in turn, steering signals for the missile are derived. By means of a helmet visor a target recognized by the pilot is designated to the seeker. The missile is guided to this target in the described manner.
During air combats with close curves ("close-in-combat") it is desirable to detect a target even at a large look angle of the seeker. However, the look angle of the seeker is, of course, limited by the design. During air combats with close curves, situations can arise, in which the target occurs under an angle of vision, which is larger than the maximum allowable look angle of the seeker. Then the target cannot be designated to the seeker head. During the further course of the curved flight, the angle of sight can be reduced to a value below the maximum allowable look angle. Then the target can be designated to the seeker head and the missile can be fired. The earlier this is made, the greater are the chances of hitting the target. If, however, the missile is fired, then it first has the tendency to align aerodynamically with the direction of the velocity vector of the missile. Then the angle of vision to the target can again exceed the maximum allowable look angle of the seeker, such that the target gets lost. The target can also be covered temporarily by clouds.